Supplemental Cash Flow Information (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Supplemental Cash Flow Information (Textuals)
Interest paid, net of amounts capitalized	$ 234.0	$ 198.0	$ 152.3
Income taxes paid, net of refunds	(109.1)	166.7	(27.9)
Accounts payable related to capital expenditures	16.7	18.2	14.7
Amortization of deferred revenue	$ 54.4	$ 34.6	$ 8.0